1. Field of the Invention
The present invention relates to haptic interfaces. More specifically, the present invention relates to incorporating haptic technology in portable electronic devices to convey different types of information to a user.
2. Background of the Invention
As the information revolution continues to unfold, more and more types of information are being communicated to a user via electronic devices. For instance, computers and input/output (I/O) devices are increasingly being incorporated into aspects of a user's life, such as for communication (cellular telephones, laptops, etc.), transportation (cars, buses, airplanes), home appliances, sports equipment, etc.
A human being typically receives information through several senses and combinations of senses such as visual, auditory, smell/taste, tactile, etc. However, traditional user interfaces for electronic/computing devices almost exclusively use a visual channel for displaying information to a user, combined with auditory signals for conveying limited types of information. For instance, most electronic devices include an LCD, LED, or equivalent display to communicate images and words to a user, or at least LED indicators to indicate a status of the device. Most modern portable computers have high-resolution displays that are able to communicate a plethora of information simultaneously via a rich visual interface. Mobile devices such as cellular telephones have adopted this rich visual interface. For instance, devices such as Apple's iPhone® or other smart phones are essentially smaller versions of traditional desktop computer interfaces.
However, one problem with this approach is the underlying assumption that the visual sense of the user will always be available. Today's average mobile users finds themselves in an increasing number of scenarios where looking at the phone may be unsafe or socially unacceptable, or where the visual sense is otherwise occupied. For instance, looking at a user interface while driving is a known hazard, and laws in many states prohibit usage of mobile consumer electronics while operating a motor vehicle. Diverting one's visual attention from a presenter at a meeting, for instance, is an additional faux pas that is considered disruptive or socially unacceptable. In some cases, visually impaired users cannot even see visual interfaces, much less use them.
Another problem with the visual channel is that it is only useful for viewing certain types of information such as text, charts or maps. For instance, in human-to-human interaction, mobile user interfaces may be effective in conveying semantic information (i.e. where/when to meet up for lunch), but are relatively poor communication channels for conveying intent and emotion. Orthographic conventions and emoticons can be used to approximate this type of information to some extent, but clearly do not attain the same level of richness as face-to-face communication.
A potential alternative to traditional visual-based communication is to use auditory messages. Currently, a number of mobile devices use text-to-speech software to convert text messages to auditory messages. Other services allow users to record and send each other auditory messages. Since these auditory messages are simply messages read aloud, they are easy to understand, and do not divert the user's attention from a task requiring visual attention, such as driving.
However, this auditory approach to providing feedback still has a number of drawbacks. First, a user's visual attention may be required to manipulate the device, which can be unsafe when driving or socially unacceptable when in a meeting. Furthermore, audio cannot always be heard because of environmental factors such as a busy road, or at a loud concert. Moreover, audio information may not always be appropriate in settings such a business meeting, where both the auditory and visual senses are occupied by a presenter.
A third type of output in use today involves the user of tactile feedback. A common example of this type of feedback is vibrating mobile devices. However, the functionality here is limited. The only alert that is prevalent in use today is a vibrating indicator that another party is trying to reach the user, for instance, by alerting an incoming call or message. Further, the potential of these vibrating mechanisms are not currently fully exploited to communicate any additional information besides semantic or alert information. Mapping messages to phone vibrators is a non-trivial process. The vibrators on commodity mobile phones only turn on and off, and present software API provides no mechanism for adjusting the vibrating signal.
Therefore, what is needed is means to communicate a variety of information to a user using a physical sensation while the user's auditory and visual senses are otherwise occupied.